Normally I shoot raw only (no JPEG). While out shooting the Leica SL in the field on my recent trip, I noticed that when I zoomed in fully to check sharpness, the zoomed in image quality with DNG was awful, with mangled detail and mottled color smearing. The degradation varies by image, with some images looking ~OK and some looking truly awful.
I knew from past experience with other cameras that setting the camera to RAW+JPEG would yield a far superior zoomed-in image.
Setting the Leica SL to DNG+JPEG highest quality results in a zoomed-in experience with far superior image quality.
As a bonus, DNG+JPEG also yields a superior histogram; the DNG-only histogram can be notched and coarse, but with DNG+JPEG the histogram has smooth countours (again, not always but definitely bad with some images).
Later, I just throw away the JPEG files. That this crudely wasteful kludge is required is absurd, but it’s very helpful when reviewing focus/sharpness in the field.